<!DOCTYPE html>
<script src="../include.js"></script>
<script>
    test(() => {
        try {
            document.defaultView.getComputedStyle(document.documentElement, null).setProperty("foo", "bar");
            println("FAIL");
        } catch (e) {
            println(`Calling setProperty() on a computed CSSStyleDeclaration throws error of type: ${e.name}`);
        }

        try {
            document.defaultView.getComputedStyle(document.documentElement, null).removeProperty("foo");
            println("FAIL");
        } catch (e) {
            println(`Calling removeProperty() on a computed CSSStyleDeclaration throws error of type: ${e.name}`);
        }
    });
</script>
